Hi. I am using the right drivers from Linux
Lubuntu CPU is 80% to 100% on YT 4K video

on YouTube playing on 4K @60fps very high CPU
i tried h264ify still lag and very high CPU
tried different Internet browser still lag and very high CPU.
tried patched chromium still lag very high CPU

i don't have this problem with windows 10 (64bit)
on windows 10 64bit CPU usage is 10% or 20% to 30% on YouTube 4K video
all web browsers work excellent on windows 10, only problem is Memory (RAM) on windows 10